Fluid flow control valves have been available and in usage for many years, primarily for providing some regulation to the flow of fluids through a flow line. Numerous patents have been issued upon this type of technology, and even recently, as illustrated in the U.S. patents U.S. Pat. No. 4,442,997; U.S. Pat. No. 4,453,700; U.S. Pat. No. 4,541,610; U.S. Pat. No. 4,693,450; and U.S. Pat. No. 4,695,034.
A review of the designs of these earlier flow control valves readily discloses varying degrees of complexity, in their structure and methods of operation, with most of such valves being of rather precision and integrated assembly, making them rather complex instruments of usage. In fact, due to their complex construction, few, if any, known flow control valves could or can be used in a nozzle of a fuel dispensing system, as for use in the routine delivery of gasoline to the customer.
The general construction of flow control valves are usually designed incorporating the principle that some force is exerted upon a valve member thereby urging it into or against a valve seat. Such valve-urging force is normally counteracted by a resilient member, such as spring, or other biasing means, within a valve body. In such flow regulators both the valve and the valve seat are machined to precise tolerances to provide for a close and fluid tight fit.
Through the construction of this current invention, a flow control valve is provided which does not have a valve seat, and a consequence of this quite different approach is that it is much simpler of construction, and lesser expensive to manufacture, than such valves as heretofore have been made.